If one day you feel like you're stupid, remember the uncle who spent $18,300 on absolutely nothing.

Italian artist Salvatore Garau managed to sell "Io sono" ("I am"), a completely invisible sculpture made, according to himself, of air, emptiness, and spiritual energy.
The auction took place at Art-Rite in Milan, and yes... someone actually paid for it.
The piece has no physical body, cannot be touched nor viewed.
The buyer only received a certificate of authenticity and a somewhat curious instruction: to reserve an empty space of 1.5 x 1.5 meters in their home to "place" the artwork.
Garau defended his creation, arguing that emptiness does not equal absence, but rather a manifestation of presence in its purest form.
While some praise it as top-tier conceptual art, others see it as the most elegant scam of modern times.